A Study to Evaluate the Effects of KarXT on the Drug Levels of Midazolam, Fexofenadine, and Digoxin

A Phase 1, 3-part, Open-label Study to Evaluate the Effects of KarXT Administration on the Pharmacokinetics of Midazolam, Fexofenadine, and Digoxin in Healthy Adult Participants

The purpose of this study is to evaluate the effects of KarXT administration on the drug levels of midazolam, fexofenadine, and digoxin in healthy adult participants.

Inclusion Criteria:

• Participants must be healthy male and female (INOCBP) as determined by no clinically significant deviation from normal in medical history, physical examination, 12-lead ECG, VS, and clinical laboratory determinations.
• Participants must have BMI of 18.0 to 32.0 kg/m2.

Exclusion Criteria:

• Participants must not have organ dysfunction or any clinically significant deviation from normal in physical examination, VS, ECG, or clinical laboratory determinations beyond what is consistent with the target population reference ranges.
• Participants must not have cirrhosis, biliary duct abnormalities, hepatobiliary carcinoma, and/or active hepatic viral infections based on the LFT results.
• Participants must not have any other significant acute or chronic medical illness, as assessed by the investigator.
• Participants must not have history or high risk of urinary retention, gastric retention, or narrow-angle glaucoma or known history of prostate hypertrophy or nocturia.
• Participants must not have current or recent (within 3 months of first study intervention administration) GI disease that could possibly affect drug ADME (eg, bariatric procedure).
• Participants must not have any major surgery, including GI surgery (eg, cholecystectomy and any other GI surgery) that could impact upon the absorption of study intervention (uncomplicated appendectomy and hernia repair are acceptable).
• Participants must not have history of active GI obstructive disorder.
• Participants must not have history of bladder stones.
• Participants must not have history of recurrent urinary tract infections.
• Other protocol-defined Inclusion/Exclusion criteria apply.